export to sdfits of data with xpol no longer working

[Malte Marquarding]

During the introduction of npol to PKSrec the behaviour seem to have changed.

I can no longer export to sdfits.

The data is in trunk/test/data/parkes-pol.rpf

Could you look into this please. When I tried to change the STwriter to only pass through npol=2 this breaks the MS2writer.

[Malte Marquarding]

ASAP uses npol=4 for linears and cross (XX, YY, Re(XY), Imag(XY), the pksio library uses n=2 + one complex (pksrec.spectra, pksrec.xpol). It seems that the MS2 writer needs n=4+1 whereas the SDFits writer needs n=2+1. It should consistently pass n=2+1 everywhere. I have assigned this to you Takeshi because you did most of the work on the MS2 writer.

[Takeshi Nakazato]

Actually, for CASA side, we don't use PKSMS2writer any more. We have MSWriter instead. Also, we rarely use MS2SDWriter, which exports data to SDFITS format. Therefore, I didn't change those classes for the long term (~ 2 years).

Anyway, I will look into this.

[Malte Marquarding]

Oops my mistake. I mustn't have tested correctly. It looks like export/import loop for MSWriter for data with xpol doesn't work.

s = scantable("data/parkes-pol.rpf")
s.save('t.ms','MS2', True)
s2 = scantable('t.ms')
s2.plot()
Loading new plotter
SEVERE: Illegal polarisation index

I will fix the SDFits related issue separately.

[Takeshi Nakazato]

OK. I will look at MSWriter/MSFiller.

[Malte Marquarding]

r2652 fixes the SDFITS part of the issue.

[Takeshi Nakazato]

Malte,

I couldn't reproduce an error. In casapy, I did the following procedure and worked fine:

s = sd.scantable('parkes-pol.rpf',False)
s.save('t.ms','MS2')
s2 = sd.scantable('t.ms',False)
sd.plotter.plot(s2)

[Malte Marquarding]

Replying to TakeshiNakazato:

Malte,

I couldn't reproduce an error. In casapy, I did the following procedure and worked fine:

s = sd.scantable('parkes-pol.rpf',False)
s.save('t.ms','MS2')
s2 = sd.scantable('t.ms',False)
sd.plotter.plot(s2)

Is that including the fix I applied to the plotter yesterday?

[Takeshi Nakazato]

Is that including the fix I applied to the plotter yesterday?

Yes, I checked out latest code and built it. MSWriter worked fine. I also tested PKSMS2writer to export data to MS. As a result, it was failed to export with error of "mismatch in #dim of array of column DATA". However, in my understanding, PKSMS2writer is not used now.

[Takeshi Nakazato]

I also tested with turning on auto-averaging when scantable object is created, i.e.,

s = sd.scantable('parkes-pol.rpf',True)
s.save('t.ms','MS2')
s2 = sd.scantable('t.ms',True)
sd.plotter.plot(s2)

It also worked fine.